Results for "Kshitij Dwivedi"

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Representation Similarity Analysis for Efficient Task taxonomy & Transfer LearningApr 26 2019Transfer learning is widely used in deep neural network models when there are few labeled examples available. The common approach is to take a pre-trained network in a similar task and finetune the model parameters. This is usually done blindly without ... More
The Algonauts Project: A Platform for Communication between the Sciences of Biological and Artificial IntelligenceMay 14 2019In the last decade, artificial intelligence (AI) models inspired by the brain have made unprecedented progress in performing real-world perceptual tasks like object classification and speech recognition. Recently, researchers of natural intelligence have ... More
Deep Anchored Convolutional Neural NetworksApr 22 2019Convolutional Neural Networks (CNNs) have been proven to be extremely successful at solving computer vision tasks. State-of-the-art methods favor such deep network architectures for its accuracy performance, with the cost of having massive number of parameters ... More
Some results on Ricci-Bourguignon and Ricci-Bourguignon almost solitonsSep 28 2018We prove some results for the solitons of the Ricci-Bourguignon flow, generalizing corresponding results for Ricci solitons. Taking motivation from Ricci almost solitons, we then introduce the notion of Ricci-Bourguignon $almost$ solitons and prove some ... More
Minimal Hypersurfaces in nearly $\mathrm{G}_2$ ManifoldsMay 10 2018Oct 19 2018We study hypersurfaces in a nearly $\mathrm{G}_2$ manifold. We define various quantities associated to such a hypersurface using the $\mathrm{G}_2$ structure of the ambient manifold and prove several relationships between them. In particular, we give ... More
Fermi arc reconstruction at junctions between Weyl semimetalsNov 16 2017Feb 22 2018We analyze junctions between noninteracting fermionic topological phases. A closed-form condition for the existence of localized modes at the interface is derived using the transfer matrix approach. These analytical conditions as well as numerical exact ... More
Embedding and partial resolution of complex cones over Fano threefoldsMay 23 2015Oct 03 2016This work deals with the study of embeddings of toric Calabi-Yau fourfolds which are complex cones over the smooth Fano threefolds. In particular, we focus on finding various embeddings of Fano threefolds inside other Fano threefolds and study the partial ... More
Picone's Identity for $p$-biharmonic operator and Its ApplicationsMar 18 2015Apr 02 2015In this article we prove the nonlinear analogue of Picone's identity for $p-$biharmonic operator. As an application of our result we show that the Morse index of the zero solution to a $p-$biharmonic boundary value problem is $0$. We also prove a Hardy ... More
Consistent estimation of the spectrum of trace class data augmentation algorithmsNov 02 2017Nov 29 2017Markov chain Monte Carlo is widely used in a variety of scientific applications to generate approximate samples from intractable distributions. A thorough understanding of the convergence and mixing properties of these Markov chains can be obtained by ... More
Wishart distributions for decomposable covariance graph modelsMar 09 2011Gaussian covariance graph models encode marginal independence among the components of a multivariate random vector by means of a graph $G$. These models are distinctly different from the traditional concentration graph models (often also referred to as ... More
Classifying Radio Galaxies with Convolutional Neural NetworkMay 09 2017We present the application of deep machine learning technique to classify radio images of extended sources on a morphological basis using convolutional neural networks. In this study, we have taken the case of Fanaroff-Riley (FR) class of radio galaxies ... More
Rates of convergence of some multivariate Markov chains with polynomial eigenfunctionsJun 23 2009We provide a sharp nonasymptotic analysis of the rates of convergence for some standard multivariate Markov chains using spectral techniques. All chains under consideration have multivariate orthogonal polynomial as eigenfunctions. Our examples include ... More
Sparse Matrix Decompositions and Graph CharacterizationsNov 28 2011Mar 22 2012The question of when zeros (i.e., sparsity) in a positive definite matrix $A$ are preserved in its Cholesky decomposition, and vice versa, was addressed by Paulsen et al. in the Journal of Functional Analysis (85, pp151-178). In particular, they prove ... More
Convergence analysis of some multivariate Markov chains using stochastic monotonicityFeb 22 2013We provide a nonasymptotic analysis of convergence to stationarity for a collection of Markov chains on multivariate state spaces, from arbitrary starting points, thereby generalizing results in [Khare and Zhou Ann. Appl. Probab. 19 (2009) 737-777]. Our ... More
Convergence properties of Gibbs samplers for Bayesian probit regression with proper priorsFeb 27 2016Mar 05 2016The Bayesian probit regression model (Albert and Chib (1993)) is popular and widely used for binary regression. While the improper flat prior for the regression coefficients is an appropriate choice in the absence of any prior information, a proper normal ... More
Research News -- Quantum Mechanical Entanglement and Tests of CPT Theorem with Neutral Mesons at e+ e- CollidersSep 02 2007We review the recent confirmation of quantum entanglement in e+ e- collisions at the BELLE experiment at KEK-B in Japan with neutral B- mesons, and at the KLOE experiment at the DAFNE in Italy with neutral K- mesons. Such effects in the latter system ... More
A Note on the Complexity of Model-Checking Bounded Multi-Pushdown SystemsDec 06 2012In this note, we provide complexity characterizations of model checking multi-pushdown systems. Multi-pushdown systems model recursive concurrent programs in which any sequential process has a finite control. We consider three standard notions for boundedness: ... More
Extremal subgraphs of the $d$-dimensional grid graphFeb 26 2013For each natural number $n$ we determine, both asymptotically and exactly, the maximum number of edges an induced subgraph of order $n$ of the $d$-dimension a grid graph ${\ints}^d$ can have. The asymptotic bound is obtained by using a theorem Bollob\'{a}s ... More
Equilibration problem for the generalized Langevin equationApr 06 2006Aug 24 2007We consider the problem of equilibration of a single oscillator system with dynamics given by the generalized Langevin equation. It is well-known that this dynamics can be obtained if one considers a model where the single oscillator is coupled to an ... More
Convergence of cyclic coordinatewise l1 minimizationApr 21 2014Jan 29 2015We consider the general problem of minimizing an objective function which is the sum of a convex function (not strictly convex) and absolute values of a subset of variables (or equivalently the l1-norm of the variables). This problem appears exten- sively ... More
Communication trade-offs for synchronized distributed SGD with large step sizeApr 25 2019Synchronous mini-batch SGD is state-of-the-art for large-scale distributed machine learning. However, in practice, its convergence is bottlenecked by slow communication rounds between worker nodes. A natural solution to reduce communication is to use ... More
Physics Informed Extreme Learning Machine (PIELM) -- A rapid method for the numerical solution of partial differential equationsJul 08 2019There has been rapid progress recently on the application of deep networks to the solution of partial differential equations, collectively labelled as Physics Informed Neural Networks (PINNs). In this paper, we develop Physics Informed Extreme Learning ... More
GCD Computation of n IntegersJul 25 2014Greatest Common Divisor (GCD) computation is one of the most important operation of algorithmic number theory. In this paper we present the algorithms for GCD computation of $n$ integers. We extend the Euclid's algorithm and binary GCD algorithm to compute ... More
Generating protected fingerprint template utilizing coprime mapping transformationMay 25 2018The identity of a user is permanently lost if biometric data gets compromised since the biometric information is irreplaceable and irrevocable. To revoke and reissue a new template in place of the compromised biometric template, the idea of cancelable ... More
Partial resolution of complex cones over Fano ${\cal{B}}$Jun 16 2012Oct 23 2013In our recent paper arXiv:1108.2387, we systematized inverse algorithm to obtain quiver gauge theory living on the M2-branes probing the singularities of special kind of Calabi-Yau four-folds which were complex cones over toric Fano $\mathbb{P}^3$, ${\cal{B}}_1$, ... More
Naked Singularity, Black-hole and the Mass Loss in a Spherically Symmetric Gravitational CollapseNov 07 2001A distinguishable physical property between a naked singularity and a black-hole, formed during a gravitational collapse has important implications for both experimental and theoretical relativity. We examine the energy radiated during the spherically ... More
Adaptive Scheduling in Real-Time Systems Through Period AdjustmentDec 14 2012Real time system technology traditionally developed for safety critical systems, has now been extended to support multimedia systems and virtual reality. A large number of real-time application, related to multimedia and adaptive control system, require ... More
Inverse algorithm and M2-brane theoriesAug 11 2011Nov 01 2011Recent paper arXiv:1103.0553 studied the quiver gauge theories on coincident $M2$ branes on a singular toric Calabi-Yau 4-folds which are complex cone over toric Fano 3-folds. There are 18 toric Fano manifolds but only 14 toric Fano were obtained from ... More
Some remarks on the qualitative questions for biharmonic equationsDec 21 2013Mar 19 2014In this article, we obtain several interesting remarks on the qualitative questions such as stability criteria, Morse index, Picone's identity for biharmonic equations.
Simple 8085 microprocessor compatible I/O cardOct 19 2004A simple interfacing project with the 8085-microprocessor kits available in under graduate college labs has been discussed. The interface card to study the I-V characteristics of a p-n diode emphasizes how the microprocessor can be used to do experiments ... More
Stability of positive solutions to biharmonic equations on Heisenberg groupJun 21 2016Sep 06 2016In this note, we establish the existence of a positive solution and its stability to the following problem $$\Delta_{\mathbb{H}^n}^2u=a(\xi)u-f(\xi,u)\text{ in }\Omega, \,\,\, u|_{\partial\Omega} = 0 =\left.\Delta_{\mathbb{H}^n} u|_{\partial\Omega},$$ ... More
An Efficient Multiplication Algorithm Using Nikhilam MethodJul 10 2013Multiplication is one of the most important operation in computer arithmetic. Many integer operations such as squaring, division and computing reciprocal require same order of time as multiplication whereas some other operations such as computing GCD ... More
Singular Adams inequality for biharmonic operator on Heisenberg Group and its applicationsJun 21 2016Feb 09 2017The goal of this paper is to establish singular Adams type inequality for biharmonic operator on Heisenberg group. As an application, we establish the existence of a solution to \begin{equation*} \Delta_{\mathbb{H}^n}^2 u=\frac{f(\xi,u)}{\rho(\xi)^a}\,\,\text{ ... More
A spectral analytic comparison of trace-class data augmentation algorithms and their sandwich variantsFeb 23 2012The data augmentation (DA) algorithm is a widely used Markov chain Monte Carlo algorithm that is easy to implement but often suffers from slow convergence. The sandwich algorithm is an alternative that can converge much faster while requiring roughly ... More
Significant Results from SUMER/SOHONov 08 2006We briefly outline recent observations by solar spacecraft such as Yohkoh, SOHO, TRACE, and RHESSI, which have revolutionized what we know and don't know about the Sun. We then present some significant results, mainly from SUMER/SOHO but also complimentary ... More
Singular Adams inequality for biharmonic operator on Heisenberg Group and its applicationsJun 21 2016The goal of this paper is to establish singular Adams type inequality for biharmonic operator on Heisenberg group. As an application, we establish the existence of a solution to \begin{equation*} \Delta_{\mathbb{H}^n}^2 u=\frac{f(\xi,u)}{\rho(\xi)^a}\,\,\text{ ... More
Unusual ferromagnetism in nanoparticles of doped oxides and manganitesNov 08 2011The observation of unusually large ferromagnetism in the nanoparticles of doped oxides and enhanced ferromagnetic tendencies in manganite nanoparticles have been in focus recently. For the transition metal-doped oxide nanoparticles a phenomenological ... More
Chiral kinetic theory and anomalous hydrodynamics in even spacetime dimensionsJun 15 2016We study the hydrodynamics of a gas of noninteracting Weyl fermions coupled to the electromagnetic field in $(2N + 1) + 1$ spacetime dimensions using the chiral kinetic theory, which encodes the gauge anomaly in the Chern character of the nonabelian Berry ... More
A novel hybrid score level and decision level fusion scheme for cancelable multi-biometric verificationMay 26 2018In spite of the benefits of biometric-based authentication systems, there are few concerns raised because of the sensitivity of biometric data to outliers, low performance caused due to intra-class variations and privacy invasion caused by information ... More
Trees and Islands -- Machine learning approach to nuclear physicsJul 23 2019We implement machine learning algorithms to nuclear data. These algorithms are purely data driven and generate models that are capable to capture intricate trends. Gradient boosted trees algorithm is employed to generate a trained model from existing ... More
Field of a Radiation DistributuionOct 12 1997Jun 20 1998General relativistic spherically symmetric matter field with a vanishing stress energy scalar is analyzed. Procedure for generating exact solutions of the field equations for such matter distributions is given. It is further pointed out that all such ... More
Classical chiral kinetic theory and anomalies in even space-time dimensionsAug 21 2013We propose a classical action for the motion of massless Weyl fermions in a background gauge field in (2N+1)+1 spacetime dimensions. We use this action to derive the collisionless Boltzmann equation for a gas of such particles, and show how classical ... More
Phase Space Entanglement SpectrumFeb 26 2018We generalize the position- and momentum-space entanglement cuts to a family of cuts corresponding to regions in the classical phase space. We explicitly compute the entanglement spectra of free fermionic many-body wavefunctions for a family of phase ... More
Is toric duality a Seiberg-like duality in (2+1)-d ?Jan 13 2014Jun 27 2014We show that not all $(2+1)$ dimensional toric phases are Seiberg-like duals. Particularly, we work out superconformal indices for the toric phases of Fanos ${\cal{C}}_3$, ${\cal{C}}_5$ and ${\cal{B}}_2$. We find that the indices for the two toric phases ... More
Stability of positive solutions to biharmonic equations on Heisenberg groupJun 21 2016Apr 27 2019In this note, we establish the existence of a positive solution and its stability to the following problem $$\Delta_{\mathbb{H}^n}^2u=a(\xi)u-f(\xi,u)\text{ in }\Omega, \,\,\, u|_{\partial\Omega} = 0 =\left.\Delta_{\mathbb{H}^n} u|_{\partial\Omega},$$ ... More
Are the Michelson--Morley experiment, the relativistic Doppler effect as well as the aberration of light consistent with an aether concept, and can the aether drift speed be determined?Mar 11 2016After an overview of various citations relevant in the context of photon propagation, the relativistic longitudinal Doppler effect and the addition theorem of velocities are first derived taking into account momentum and energy conservation. Clocks, the ... More
The Aharonov-Bohm effect: A quantum or a relativistic phenomenon?Aug 23 2014Oct 20 2016The Aharonov-Bohm effect is considered by most authors as a quantum effect, but a generally accepted explanation does not seem to be available. The phenomenon is studied here under the assumption that hypothetical electric dipole distributions configured ... More
Emergence of clustering: Role of inhibitionMay 10 2014Sep 19 2014Though biological and artificial complex systems having inhibitory connections exhibit high degree of clustering in their interaction pattern, the evolutionary origin of clustering in such systems remains a challenging problem. Using genetic algorithm ... More
Connecting the dots: Time-reversal symmetric Weyl Semimetals with tunable Fermi arcsAug 03 2016We propose a one-parameter family of noninteracting lattice models for Weyl semimetals with 4 Weyl nodes and tunable Fermi arcs. These 2-band model Hamiltonians are time-reversal symmetric with $\mathrm{T}^2 = + 1$, and tuning the parameter changes the ... More
Influence of electronic structure parameters on the electrical transport and magnetic properties of $Y_{2-x}Bi_xIr_2O_7$ pyrochlore iridatesMay 07 2019We report the systematic study of structural, magnetic and electrical transport properties of $Y_{2-x}Bi_xIr_2O_7$ (x = 0.0, 0.1, 0.2, 0.3) pyrochlore iridates. The chemical doping enhances electrical conductivity and antiferromagnetic correlation substantially. ... More
Coexistence of high electrical conductivity and weak ferromagnetism in Cr doped Y$_2$Ir$_2$O$_7$ pyrochlore iridateApr 11 2019We report the structural, magnetic and electrical transport properties of Y$_2$Ir$_{2-x}$Cr$_x$O$_7$ pyrochlore iridates. The chemical doping leads to order of magnitude enhancement of electrical conductivity. The introduction of Cr3+ at Ir4+ site tends ... More
Emergence of (bi)multi-partiteness in networks having inhibitory and excitatory couplingsApr 03 2015Jul 15 2015(Bi)multi-partite interaction patterns are commonly observed in real world systems which have inhibitory and excitatory couplings. We hypothesize these structural interaction pattern to be stable and naturally arising in the course of evolution. We demonstrate ... More
Photon in a cavity -- a GedankenexperimentJul 09 2013The inertial and gravitational mass of electromagnetic radiation (i.e., a photon distribution) in a cavity with reflecting walls has been treated by many authors for over a century. After many contending discussions, a consensus has emerged that the mass ... More
Solar coronal plumes and the fast solar windJan 08 2015The spectral profiles of the coronal Ne viii line at 77 nm have different shapes in quiet-Sun regions and coronal holes (CHs). A single Gaussian fit of the line profile provides an adequate approximation in quiet-Sun areas, whereas a strong shoulder on ... More
Michelson-Morley experiment, Doppler effect, aberration of light and the aether conceptMar 11 2016Jan 05 2018After an overview of various citations relevant in the context of photon propagation, the relativistic Doppler effect and the addition theorem of velocities are first derived taking into account momentum and energy conservation. Clocks and the aberration ... More
Estimating Achievable Range of Ground Robots Operating on Single Battery Discharge for Operational Efficacy AmeliorationNov 07 2018Mobile robots are increasingly being used to assist with active pursuit and law enforcement. One major limitation for such missions is the resource (battery) allocated to the robot. Factors like nature and agility of evader, terrain over which pursuit ... More
On the potential energy in a gravitationally bound two-body system with arbitrary mass distributionFeb 12 2015The potential energy problem in a gravitationally bound two-body system has recently been studied in the framework of a proposed impact model of gravitation (Wilhelm and Dwivedi 2015). The result was applied to the free fall of the so-called Mintrop--Ball ... More
On the potential energy in an electrostatically bound two-body systemAug 30 2014The potential energy problem in an electrostatically bound two-body system is studied in the framework of a recently proposed impact model of the electrostatic force and in analogy to the potential energy in a gravitationally bound system. The physical ... More
Balanced condition in networks leads to Weibull statisticsNov 27 2013The importance of the balance in inhibitory and excitatory couplings in the brain has increasingly been realized. Despite the key role played by inhibitory-excitatory couplings in the functioning of brain networks, the impact of a balanced condition on ... More
Extreme-value statistics of networks with inhibitory and excitatory couplingsApr 27 2013Inspired by the importance of inhibitory and excitatory couplings in the brain, we analyze the largest eigenvalue statistics of random networks incorporating such features. We find that the largest real part of eigenvalues of a network, which accounts ... More
A convex pseudo-likelihood framework for high dimensional partial correlation estimation with convergence guaranteesJul 20 2013Aug 14 2014Sparse high dimensional graphical model selection is a topic of much interest in modern day statistics. A popular approach is to apply l1-penalties to either (1) parametric likelihoods, or, (2) regularized regression/pseudo-likelihoods, with the latter ... More
Rejoinder: Gibbs Sampling, Exponential Families and Orthogonal PolynomialsAug 28 2008We are thankful to the discussants for their hard, interesting work. The main purpose of our paper was to give reasonably sharp rates of convergence for some simple examples of the Gibbs sampler. We chose examples from expository accounts where direct ... More
Posterior Graph Selection and Estimation Consistency for High-dimensional Bayesian DAG ModelsNov 03 2016Covariance estimation and selection for high-dimensional multivariate datasets is a fundamental problem in modern statistics. Gaussian directed acyclic graph (DAG) models are a popular class of models used for this purpose. Gaussian DAG models introduce ... More
High-dimensional posterior consistency for hierarchical non-local priors in regressionSep 19 2017Feb 22 2019The choice of tuning parameters in Bayesian variable selection is a critical problem in modern statistics. In particular, for Bayesian linear regression with non-local priors, the scale parameter in the non-local prior density is an important tuning parameter ... More
Estimating the spectral gap of a trace-class Markov operatorApr 04 2017Apr 04 2019The utility of a Markov chain Monte Carlo algorithm is, in large part, determined by the size of the spectral gap of the corresponding Markov operator. However, calculating (and even approximating) the spectral gaps of practical Monte Carlo Markov chains ... More
Posterior Graph Selection and Estimation Consistency for High-dimensional Bayesian DAG ModelsNov 03 2016Oct 11 2017Covariance estimation and selection for high-dimensional multivariate datasets is a fundamental problem in modern statistics. Gaussian directed acyclic graph (DAG) models are a popular class of models used for this purpose. Gaussian DAG models introduce ... More
A Bayesian Approach to Joint Estimation of Multiple Graphical ModelsFeb 10 2019Jul 02 2019The problem of joint estimation of multiple graphical models from high dimensional data has been studied in the statistics and machine learning literature, due to its importance in diverse fields including molecular biology, neuroscience and the social ... More
Knowledge-incorporating ESIM models for Response Selection in Retrieval-based Dialog SystemsJul 11 2019Goal-oriented dialog systems, which can be trained end-to-end without manually encoding domain-specific features, show tremendous promise in the customer support use-case e.g. flight booking, hotel reservation, technical support, student advising etc. ... More
On the gravitational redshiftJul 01 2013Apr 16 2014The study of the gravitational redshift\,---\,a relative wavelength increase of $\approx 2 \times 10^{-6}$ was predicted for solar radiation by Einstein in 1908\,---\,is still an important subject in modern physics. In a dispute whether or not atom interferometry ... More
Impact models of gravitational and electrostatic forces: Potential energies, atomic clocks, gravitational anomalies and redshiftApr 10 2018The far-reaching gravitational force is described by a heuristic impact model with hypothetical massless entities propagating at the speed of light in vacuum and transferring momentum and energy be- tween massive bodies through interactions on a local ... More
A test for second order stationarity of a time series based on the Discrete Fourier Transform (Technical Report)Nov 25 2009We consider a zero mean discrete time series, and define its discrete Fourier transform at the canonical frequencies. It is well known that the discrete Fourier transform is asymptotically uncorrelated at the canonical frequencies if and if only the time ... More
Non-Hermitian systems and topology: A transfer matrix perspectiveDec 05 2018Mar 05 2019Topological phases of Hermitian systems are known to exhibit intriguing properties such as the presence of robust boundary states and the famed bulk-boundary correspondence. These features can change drastically for their non-Hermitian generalizations, ... More
Gibbs Sampling, Exponential Families and Orthogonal PolynomialsAug 28 2008We give families of examples where sharp rates of convergence to stationarity of the widely used Gibbs sampler are available. The examples involve standard exponential families and their conjugate priors. In each case, the transition operator is explicitly ... More
Active Imitation Learning via Reduction to I.I.D. Active LearningOct 16 2012In standard passive imitation learning, the goal is to learn a target policy by passively observing full execution trajectories of it. Unfortunately, generating such trajectories can require substantial expert effort and be impractical in some cases. ... More
A Bayesian Approach to Joint Estimation of Multiple Graphical ModelsFeb 10 2019The problem of joint estimation of multiple graphical models from high dimensional data has been studied in the statistics and machine learning literature, due to its importance in diverse fields including molecular biology, neuroscience and the social ... More
Consistent Bayesian Sparsity Selection for High-dimensional Gaussian DAG Models with Multiplicative and Beta-mixture PriorsMar 08 2019Estimation of the covariance matrix for high-dimensional multivariate datasets is a challenging and important problem in modern statistics. In this paper, we focus on high-dimensional Gaussian DAG models where sparsity is induced on the Cholesky factor ... More
Automatic Generation of Precise and Useful Commutativity Conditions (Extended Version)Feb 23 2018Reasoning about commutativity between data-structure operations is an important problem with applications including parallelizing compilers, optimistic parallelization and, more recently, Ethereum smart contracts. There have been research results on automatic ... More
Bayesian inference for Gaussian graphical models beyond decomposable graphsMay 04 2015Bayesian inference for graphical models has received much attention in the literature in recent years. It is well known that when the graph G is decomposable, Bayesian inference is significantly more tractable than in the general non-decomposable setting. ... More
Long period slow MHD waves in the solar wind source regionDec 19 2006Dec 17 2007We consider compressive viscosity and thermal conductivity to study the propagation and dissipation of long period slow longitudinal MHD waves in polar coronal holes. We discuss their likely role in the line profile narrowing, and in the energy budget ... More
An impact model of the electrostatic force: Coulomb's law re-visitedOct 05 2013May 27 2014The electrostatic force is described in this model by the action of electric dipole distributions on charged particles. The individual hypothetical dipoles are propagating at the speed of light in vacuum transferring momentum and energy between charges ... More
Counting basic-irreducible factors mod $p^k$ in deterministic poly-time and $p$-adic applicationsFeb 20 2019Finding an irreducible factor, of a polynomial $f(x)$ modulo a prime $p$, is not known to be in deterministic polynomial time. Though there is such a classical algorithm that {\em counts} the number of irreducible factors of $f\bmod p$. We can ask the ... More
A gradient flow of isometric $\mathrm{G}_2$ structuresApr 22 2019We study a flow of $G_2$ structures which induce the same Riemannian metric which is the negative gradient flow of an energy functional. We prove Shi-type estimates for the torsion tensor along the flow. We show that at a finite-time singularity the torsion ... More
Rule based Part of speech Tagger for Homoeopathy Clinical realmNov 13 2011A tagger is a mandatory segment of most text scrutiny systems, as it consigned a s yntax class (e.g., noun, verb, adjective, and adverb) to every word in a sentence. In this paper, we present a simple part of speech tagger for homoeopathy clinical language. ... More
Distributed physics informed neural network for data-efficient solution to partial differential equationsJul 21 2019The physics informed neural network (PINN) is evolving as a viable method to solve partial differential equations. In the recent past PINNs have been successfully tested and validated to find solutions to both linear and non-linear partial differential ... More
On the Occurrence of Naked Singularity in Spherically Symmetric Gravitational CollapseMay 23 1994Generalizing earlier results of Joshi and Dwivedi (Commun. Math. Phys. 146, 333 (1992); Lett. Math. Phys. 27, 235 (1993)), we analyze here the spherically symmetric gravitational collapse of a matter cloud with a general form of matter for the formation ... More
Spectroscopic Diagnostics of Polar Coronal PlumesFeb 24 2009Feb 25 2009Polar coronal plumes seen during solar eclipses can now be studied with space-borne telescopes and spectrometers. We briefly discuss such observations from space with a view to understanding their plasma characteristics. Using these observations, especially ... More
Dispersion Relation for MHD Waves in Homogeneous PlasmaNov 08 2006Jun 22 2007We consider viscosity and thermal conductivity as dissipation mechanisms to derive a general dispersion relation for MHD waves propagating in a homogeneous plasma. We show that the actual dispersion relation for MHD waves in a homogeneous medium must ... More
Colossal enhancement of electrical conductivity in Y2Ir2O7 nanoparticlesNov 17 2016We present a comparative study of the magnetic and electrical properties of polycrystalline and nanocrystalline Y2Ir2O7, the latter prepared using a new chemical route. We find that reduction in particle size leads to enhanced ferromagnetism and orders ... More
IR-UWB Detection and Fusion Strategies using Multiple Detector TypesJan 02 2015Mar 01 2016Optimal detection of ultra wideband (UWB) pulses in a UWB transceiver employing multiple detector types is proposed and analyzed in this paper. We propose several fusion techniques for fusing decisions made by individual IR-UWB detectors. We assess the ... More
Non-conventional porous 12CaO7Al2O3 Transparent Oxide Semiconductor: A Journey from foams to cubesJan 25 2017In the current study easy method to synthesize C12A7 particles with cubic morphology was investigated for the application of Transparent Conducting Oxide layer in thinfilm solar cell. By self-combustion method with proper amount of urea addition, cubic ... More
Optimization of synchronizability in multiplex networksJul 07 2015Feb 25 2016We investigate the optimization of synchronizability in multiplex networks and demonstrate that the interlayer coupling strength is the deciding factor for the efficiency of optimization. The optimized networks have homogeneity in the degree as well as ... More
Initial data and the end state of spherically symmetric gravitational collapseApr 28 1998Generalizing earlier results on the initial data and the final fate of dust collapse, we study here the relevance of the initial state of a spherically symmetric matter cloud towards determining its end state in the course of a continuing gravitational ... More
Exploring anomalous $hb\bar b$ and $h b\bar bγ$ couplings in the context of the LHC and an $e^+e^-$ colliderFeb 20 2017Jul 29 2017In the light of the 125 GeV Higgs ($h$) discovery at the Large Hadron Collider (LHC), one of the primary goals of the LHC and possible future colliders is to understand its interactions more precisely. Here we have studied the $h$-$b$-$\bar b$-$\gamma$ ... More
Inferring the Partial Correlation Structure of Allelic Effects and Incorporating it in Genome-wide PredictionMay 04 2017In this study, we addressed the problem of genome-wide prediction accounting for partial correlation of marker effects when the partial correlation structure, or equivalently, the pattern of zeros of the precision matrix is unknown. This problem requires ... More
Modelling correlated marker effects in genome-wide prediction via Gaussian concentration graph modelsNov 10 2016Sep 20 2017In genome-wide prediction, independence of marker allele substitution effects is typically assumed; however, since early stages of this technology it has been known that nature points to correlated effects. In statistics, graphical models have been identified ... More
A Hybrid Alternative to Gibbs Sampling for Bayesian Latent Variable ModelsAug 27 2018Gibbs sampling is a widely popular Markov chain Monte Carlo algorithm which is often used to analyze intractable posterior distributions associated with Bayesian hierarchical models. The goal of this article is to introduce an alternative to Gibbs sampling ... More
Graph Representations for Higher-Order Logic and Theorem ProvingMay 24 2019This paper presents the first use of graph neural networks (GNNs) for higher-order proof search and demonstrates that GNNs can improve upon state-of-the-art results in this domain. Interactive, higher-order theorem provers allow for the formalization ... More
Minimum Shared-Power Edge CutJun 12 2018We introduce a problem called the Minimum Shared-Power Edge Cut (MSPEC). The input to the problem is an undirected edge-weighted graph with distinguished vertices s and t, and the goal is to find an s-t cut by assigning "powers" at the vertices and removing ... More
Magnetostatics and the electric impact modelSep 30 2013Oct 20 2016The action of certain static magnetic fields on charged test particles is interpreted as a consequence of the interaction of the particles with electric dipole distributions emitted by other charged particles in relative motion. The dipole model of electric ... More
Efficiently factoring polynomials modulo $p^4$Jan 20 2019Polynomial factoring has famous practical algorithms over fields-- finite, rational \& $p$-adic. However, modulo prime powers it gets hard as there is non-unique factorization and a combinatorial blowup ensues. For example, $x^2+p \bmod p^2$ is irreducible, ... More